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991.
In a survey carried out on 229 subjects who had undergone an augmentative mammaplasty it was possible to verify a postoperative
increase in weight in 25 cases, four of which were clearly anorexic. We hypothesized that a change in perception of one's
body proportions after the insertion of implants, might have been a determinant in blocking the mechanism leading to anorexia,
or at least in the continuation of the recovering process. The aim of this article is obviously not to state that augmentative
mammaplasty can be a kind of therapy for anorexia. Instead, we want to underline how a more pleasant contour of some body
areas can have a role in solving deeper psychological problems. 相似文献
992.
Testini M Portincasa P Scacco S Piccinni G Minerva F Lissidini G Papa F Loiotila L Bonomo GM Palasciano G 《World journal of surgery》2002,26(4):493-498
Leakage of a large bowel anastomosis
remains the most serious postoperative complication in gastrointestinal
surgery. In a recent experimental study we found that surgically
induced hypoxia resulted in more derangement of a variety of
biochemical markers in the large bowel (LB) than in the small bowel
(SB). We explored the question of whether spontaneous and
agonist-induced contractility of SB and LB muscle strips was influenced
by surgical procedures and how contractility was related to energetic
oxidative metabolism capacity in smooth muscle mitochondria. Sixty male
New Zealand rabbits were operated on under general anesthesia. Segments
of ileum and colon were resected from each rabbit, and an end-to-end
anastomosis was constructed. A representative subset of segments from
SB (n = 14) and LB (n = 14) at time 0
was used as controls. Tracts containing an anastomosis were resected at
days 2, 7, and 14 after operation. At each time point, 20 segments
adjacent to the anastomosis of both SB and LB were used for
tensiometric and biochemical studies. Tensiometric studies demonstrated
modifications in the smooth muscle function at both the acute and
chronic stages with intestinal inflammation that may contribute to
surgical stress-associated abnormal motility. Biochemical data showed
that the respiratory capacity of the resected LB was more impaired than
that of the SB. In both SB and LB, changes in respiratory activity
preceded tensiometric changes. Thus abnormalities of contractility
after surgical stress are more evident in LB than SB in segments
adjacent to the anastomoses. This could be the consequence of abnormal
biochemical changes, as adenosine triphosphate (ATP) is required for
membrane potential maintenance, calcium homeostasis, and actin–myosin
interactions. 相似文献
993.
De Petris L Gianviti A Caione D Innocenzi D Edefonti A Montini G De Palo T Tozzi AE Caprioli A Rizzoni G 《Pediatric nephrology (Berlin, Germany)》2002,17(10):852-855
Verocytotoxin-producing Escherichia coli(VTEC) infections cause most cases of hemolytic uremic syndrome (HUS); 10-30% of patients, however, are negative for VTEC infection. The etiology of HUS in VTEC-negative cases remains poorly understood. Before the association between VTEC infection and HUS was recognized, sporadic cases of HUS with enterovirus infection were reported in the literature. Since May 1988, most cases of HUS in Italy have been reported to the Italian surveillance system, and in 73% of these, evidence of VTEC infection was demonstrated. The aim of this study was to determine whether the frequency of enteroviral infections was different in the acute phase of VTEC-positive and VTEC-negative HUS. Eighty-nine patients were investigated for enteroviral infection, of whom 58 were VTEC positive and 31 VTEC negative. Two serum samples from each patient were examined for seroconversion to enterovirus (coxsackie, echovirus, and picornavirus) by a complement fixation test. Serological evidence of acute infection with non-polio enterovirus was found in 33 patients (37%) [20/58 (34.5%) VTEC positive and 13/31 (41.9%) VTEC negative]. There was no statistically significant difference between the two groups. These results demonstrate that there are no significant differences for enteroviral infection in VTEC-positive and VTEC-negative patients and, therefore, enteroviral infections should not be considered a cause of HUS in VTEC-negative children. 相似文献
994.
Adami GF Civalleri D Cella F Marinari G Camerini G Papadia F Scopinaro N 《Obesity surgery》2002,12(5):623-627
Background: The authors evaluated the relationship between leptin and the clinical, anthropometric and metabolic variables
connected to the metabolic syndrome in obese individuals. Methods: A large group of patients with different degrees of obesity
was investigated: body mass index (BMI) values, serum leptin, fasting glucose and insulin, triglycerides and HDL-cholesterol
concentrations, insulin resistance index and blood pressure were measured. Results: On multiple regression analysis, serum
leptin levels appeared to be positively correlated to the BMI and to the serum HDL-cholesterol concentration. Principal component
factor analysis revealed three factors, explaining 61.3% of the total variance of the sample. General features of these factors
were: factor 1 - BMI values and serum leptin and fasting glucose concentration; factor 2 - systolic and diastolic blood pressure
and serum triglycerides and HDL-cholesterol concentration; factor 3 - fasting serum insulin concentration and insulin resistance
index. Conclusions: In obese subjects multiple factors underlie the metabolic syndrome and therefore more than one mechanism
may account for the clustering characteristics. In obese patients leptin loads only one factor, and therefore leptin does
not appear to be a key feature in the metabolic syndrome. On the contrary, multiple correlation and factor analysis data give
rise to the hypothesis that in obese patients, leptin may play a protective role against cardiovascular risk. 相似文献
995.
Enhanced ocular anti-inflammatory activity of ibuprofen carried by an Eudragit RS100 nanoparticle suspension 总被引:4,自引:0,他引:4
PURPOSE: To investigate the ocular pharmacodynamic profile of a polymer nanoparticle system loaded with sodium ibuprofen (IBU-RS) in comparison to an aqueous solution of ibuprofen lysinate (IBL) in the rabbit eye both being applied topically. METHODS: Ocular inflammation was elicited by topical application of sodium arachidonate. Inflammation was quantified according to a modified Draize test. The protein level and the number of polymorphonuclear leukocytes in the aqueous humor were assessed after 2 h from arachidonate instillation. The ibuprofen concentration in the aqueous humor was evaluated by HPLC assay. The physico-chemical properties of nanoparticles were also evaluated. RESULTS: The IBU-RS nanosuspension formulation significantly reduced the primary signs of ocular inflammation as well as significantly reducing the protein level and the number of polymorphonuclear leukocytes in the aqueous humor compared with the IBL formulation. Furthermore, the aqueous humor drug concentration from the group treated with IBU-RS was significantly higher compared to the IBL-treated group. The IBU-RS nanosuspensions showed very interesting size and surface charge values, adequate for ophthalmic administration. CONCLUSIONS: The pharmacological profile of the topical IBU-RS nanosuspension formulation described in this study indicates that the dispersion of the drug within RS polymer nanoparticles increased its ocular bioavailability and ultimately its pharmacological activity. 相似文献
996.
Toffoli G Vattovani O Cecchini P Pastori G Rinaldi G Ravalico G 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》2002,216(3):159-163
OBJECTIVE: To establish a correlation between the retinal nerve fiber layer (RNFL) thickness measured by a scanning laser polarimeter (GDx) and the pattern electroretinogram (p-ERG) amplitudes in a heterogeneous population sample composed of normal subjects, ocular hypertensive and glaucomatous patients. METHODS: 112 subjects were considered: 40 glaucomatous patients, 39 ocular hypertensive and 33 normal subjects. All were examined with the GDx, and the RNFL thickness was measured. A transient p-ERG was then recorded. RESULTS: A statistically significant correlation was observed between the RNFL thickness and the p-ERG amplitudes (p < 0.001) by means of linear regression analysis. CONCLUSION: We observed a strict correlation between the measurements of the RNFL thickness obtained with the GDx and the amplitude of the p-ERG signal. These techniques represent additional objective tools to detect an early glaucomatous damage. 相似文献
997.
Iester M Altieri M Michelson G Vittone P Calabria G Traverso CE 《Journal of glaucoma》2002,11(6):488-492
PURPOSE: To evaluate the intraobserver reproducibility of a software designed to assess retinal blood flow with the Heidelberg Retina Flowmeter (HRF). METHODS: Ten subjects were consecutively recruited, and one eye of each patient was randomly selected for study. Blood flow measurements were analyzed by using an automatic full field perfusion image analysis (AFFPIA) program, which calculates the Doppler frequency shift and hemodynamic variables (flow, volume, and velocity) for each pixel. The resulting perfusion image is processed with respect to underexposed and overexposed pixels, saccades, and retinal vessel tree. Intraobserver reproducibility was calculated for the AFFPIA program. All the optic nerve heads were horizontally divided into three sections (superior, central, and inferior). The retinal blood flow was calculated in the superior and inferior section, and each section was further divided into three areas (temporal, nasal, and rim). The blood flow was evaluated for each area. RESULTS: When the same observer analyzed the same image five times (intraobserver intraimage reproducibility), the AFFPIA coefficient of variation ranged from 0.5% to 5% in the temporal area, from 0.1% to 5.3% in the nasal area, and from 0.5 to 28% in the rim area.When the same observer analyzed three different images of the same section once (intraobserver interimage reproducibility), the AFFPIA coefficient of variation of flow measurements ranged from 1% to 7.3% in the temporal area, from 1.5% to 10% in the nasal area, and from 2 to 30% in the rim area. CONCLUSION: Retinal blood flow measured by HRF and analyzed by AFFPIA had good intraobserver reproducibility. The reproducibility was significantly better in the temporal and nasal areas than in the rim area. 相似文献
998.
999.
Martelli A Carrozzino R Mattioli F Brambilla G 《Toxicology and applied pharmacology》2002,182(3):219-225
4,4'-Methylenedianiline (MDA), an aromatic amine used in various industrial processes and previously found to induce tumor development in liver and thyroid of mice and rats, was evaluated for its DNA-damaging activity in primary cultures of hepatocytes and thyreocytes from rat and human donors. After exposure for 4 and 20 h to MDA concentrations ranging from 10 to 180 microM, a statistically significant increase in the frequency of DNA lesions was revealed by the Comet assay in primary hepatocytes and thyreocytes from donors of both species, the response being dose dependent up to 56-100 microM MDA. DNA fragmentation was more marked after 4 than after 20 h exposure in all four cell types. DNA was damaged to a lesser extent in human hepatocytes and thyreocytes than in corresponding rat cells and in both species in hepatocytes than in thyreocytes. In both rat and human hepatocytes a 20-h exposure to the same MDA concentrations elicited a modest amount of DNA repair synthesis, as evaluated by autoradiography. Evidence of a partial reduction of DNA damage, and therefore of only partial DNA repair, was observed in rat hepatocytes and in rat and human thyreocytes incubated for 16 h in MDA-free medium after a 4-h MDA treatment. A 4-h exposure to 56, 100, and 180 microM MDA did not induce DNA lesions in primary cultures of cells from three rat organs, kidney, urinary bladder mucosa, and brain, which are resistant to MDA carcinogenic activity. Under the same experimental conditions any evidence of DNA damage was absent in primary kidney and urinary bladder cells from human donors. Taken as a whole the results of this work indicate that MDA is specifically activated to DNA-damaging reactive species by hepatocytes and thyreocytes in both rats and humans and thus suggest that liver and thyroid might be the targets of the carcinogenic activity of MDA also in humans. 相似文献
1000.